The station opened in 1842 as Ashford by the South Eastern Railway (SER) as a temporary terminus of the line from London to Dover via Croydon.

There have been two significant rebuilds; in the 1960s for the South Eastern Main Line electrification, and to accommodate international services in the 1990s.

[8] A special train from London Bridge ran on 28 November 1842, and the station formally opened on 1 December, along with the rest of the line from Redhill.

[22] On 1 January 1899, as part of the formation of the South Eastern and Chatham Railway (SECR), passenger services were diverted to the former SER station and Ashford West closed.

[16] At the same time, the track was modified to give six separate approaches into the station, so that trains could pull up simultaneously.

[28][29] In November 1904, the SECR agreed to a £47,000 rebuilding of the scheme in order to accommodate Maidstone traffic, which included removing a cattle dock so trains would not have to run on part of the South Eastern Main Line.

[38] The main station buildings on either side of the line were replaced between 1963 and 1966 by a footbridge including a booking hall, newsagent and catering facilities.

[44] It was planned as a partial park and ride side, catering for up to 2,000 vehicles, and as a means of regenerating the town.

[49] To segregate passengers from domestic and international services, a dedicated entrance from the ticket barrier to the platforms was built.

[54][45][55] Before the completion of High Speed 1 in November 2007, twelve Eurostar trains a day called at Ashford, seven heading to Paris and five to Brussels.

[58] Eurostar defended the reduction, saying stopping at Ashford International added 8 minutes to journey times and required 25 people joining the train there to make it economically viable.

[66] Eurostar stated that they will resume services when commercially sensible to do so, as they will initially "focus on destinations where demand is highest".

[69] In 2022, the Members of Parliament for Ashford and Dartford, Damian Green and Gareth Johnson, met with Eurostar's CEO to persuade re-starting services, but described the meeting as "frustrating".

[70] Local councillor Derek Murphy said they were attempting to lobby the British Embassy in Paris and Brussels for a change.

[72] In 2007, a new maintenance depot, operated by Hitachi, opened to the northeast of the station, alongside the Canterbury West branch.

[74] A test train running at up to 140 miles per hour (230 km/h) covered the distance between Ashford International and St Pancras in 29 minutes.

[76][77] In 2018, Thameslink announced services from London Bridge to Ashford International via Swanley, Otford and Maidstone East.

These plans were put on hold, and then abandoned following the steep decline in rail traffic as a result of COVID lockdown.

[78] The Marshlink line from Ashford International to Ore is one of the few in the south east that has not yet been electrified, and is mostly single track beyond Appledore, which limits capacity.

The company wanted to cancel the service for some time, as it would allow them to add additional capacity between Eastbourne and Hastings, but had repeatedly faced objections from councillors along the line, including at Lewes.

[79][80] Because Ashford International connects High Speed 1 to the Marshlink line, it creates potential for a fast service from St Pancras to Hastings and Eastbourne.

In November 2017, the Secretary of State for Transport, Chris Grayling, proposed a modification of the track layout at Ashford International to accommodate such a service.

[81][82] To connect the two lines, the junction at the west end of the station would need to be rebuilt, with 25 kV 50 Hz AC overhead wires being installed along platform 2.

In July 2020, the off-peak timetable was:[86] Direct Eurostar services from St Pancras to Amsterdam Centraal did not stop at Ashford, though a connection can be made by changing at Brussels.